article: Paper is one of the most important products ever invented by man.
  The invention of paper meant that more people could be educated because more books could be printed. Paper provided an important way to communicate with knowledge.
  Paper was first made in China about 2000 years ago. In Egypt and the West, paper was not very commonly used before the year 1400. Paper was not made in southern Europe until about the year 1100. After that, the forestry country of Canada, Sweden, Norway, Finland, and the United States became the most important in paper-making. Today Finland makes the best paper in the world. And it has the biggest paper industry in the world.
  When we think of paper, we think of newspapers, books, letters, envelopes, and writing paper. So paper plays an important role in our lives.
  Paper is very good for keeping you warm, Houses are often insulated with paper. You have perhaps seen homeless men sleep on a large number of newspapers. They are insulating themselves from the cold. In Finland, in winter it is sometimes 40 degrees below zero. The farmers wear paper boots in the snow. _
question: The main idea of this passage is  _  .
options: The invention of paper the best paper The uses of paper the paper making